Anhydrous lubricant



Patented Nov. 27, 1934 PATENT OFFICE ANHYDROUS LUBRICANT Lawrence C. Brunstrum,

Chicago, Ill., and

William P. Hilliker, Hammond, Ind., assignors to Standard Oil Company, Chicago, 111., a corporation of Indiana No Drawing. Application April 26, 1932, Serial No. 607,662

5 Claims.

This invention relates to a substantially anhydrous lubricant and it pertains more particularly to a plug valve lubricant for use in steam lines.

The object of our invention is to provide a lubricant which will adhere to surfaces on which it is applied, which will form a tight seal and withstand high pressures for an extended period of time, which will be workable at all operating temperatures, which will be noncorrosive, which will bestable in long usage and which will be unaffected by hot steam or aqueous liquids.

A feature of the invention is the provision in block or stick form of a substantially anhydrous calcium soap in combination with a heavy oil and a heavy metal soap, the entire composition being admixed with a large amount of amorphous graphite. By using an extremely high graphite content we obtain excellent high temperature characteristics, and by using a heavy metal soap we obtain a lubricant which is unusually soft and workable at room temperatures. The graphite itself is a lubricant but it must be maintained in a soft and workable mass which will not leak oil dry or crumble under operating conditions. Ordinary greases will not withstand the high temperatures for which our lubricant is intended to be used. Our grease is particularly adapted to the lubrication of roll necks in steel mills where the rolls are continually sprayed with water to prevent overheating. Few lubricants will withstand the combined action of-heat and water here encountered, and we find our lead mahoganygraphite grease distinctly superior for this service.

A preferred formula is as follows:

Per cent Amorphous graphite 60 Anhydrous lime soap 5 Lead mahogany soap The graphite is preferably in the amorphous form and it may vary from about 35% to 65% of the entire composition.

The anhydrous lime soap is preferably made from acids which are split from hydrogenated fatty oils. We prefer to use an acid having a titre of about to 50, an iodine number of about 10 to 15, and a neutralization value of about 195 to 198. Such acids are produced by splitting mixtures of hydrogenated fats, such as fish oil, cottonseed oil, whale oil, rapeseed oil, corn oil, etc. We prefer to use acids of 18 carbon atoms and above, such as erucic and behemic acid. These acids are conveniently produced by the splitting of hydrogenated fish oil, particularly menhaden, containing appreciable amounts of cottonseed and/or rapeseed oil. The particular process for hydrogenating the fats and splitting the acids therefrom forms no part of the present invention. Although we prefer to use the hydro- 0 gen acids of 18 carbon atoms or more, we do not limit ourselves thereto. The amount of lime soap in the grease may vary from about 2 to 15%.

The expression lead mahogany soap refers to a product containing lead sulfonic soaps and heavy mineral oil. sulfonic acids are formed with heavy petroleum oils which are treated with concentrated sulphuric acid, or oleum, at elevated temperatures and/or for extended periods of time. 7 The preferentially water soluble sulfonic acids are removed with the sludge, and because of their green color they are called green acids. If neutralized, they are called green acid soaps. Preferentially oil soluble sulfonic acids (or soaps if they have been neutralized) are extracted from the oil'layer by means of 50% alcohol, and are preferably purified by extraction with about 50 to alcohol. The preferentially oil soluble sulfonic acids and salts (or soaps) are characterized by the mahogany color from which they derive their name. In practicing our invention we convert the sulfonic acids or soda soaps to lead soaps by neutralization with litharge or by double decomposition with lead acetate. The lead mahogany soap which is thus formed is usually contaminated with some oil and no efiort is made to separate all of the oil from the lead sulfonic soaps. The oil is preferably a viscous lubricating oil having a viscosity of 105 to 115 sec. Saybolt at 210 F. The amount of lead sulphonate in the oil is usually expressed by the amount of lead present and we prefer to use a composition containing about 3 lead. It should be understood, however, that we do not limit ourselvesto these particular proportions, viscosities or ingredients and We contemplate the use of the equivalents therefor which are well known in the art. The lead mahogany soap, or equivalent heavy metal soap, content of our lubricant may be varied from about 15 to 45%.

In preparing our lubricant we mix the dry anhydrous lime soap and graphite in a conventional grease mixer. Then at the temperature of about 300 F. or more we stir in the lead mahogany soap. When the soap has been thoroughly worked in and the mass is homogeneous, it is cast into blocks and is finally exuded through an orifice or die in the form of sticks, which are preferably coated with powdered mica to facilitate handling.

The anhydrous lime soap is prepared by neutralization of acids from hydrogenated oilsas above described, or it may be prepared by the saponification of hydrogenated fats. In either event the graphite plays an important role in providing reserve lubrication at temperatures above the decomposition temperature of the oils. At the same time the lead mahogany soap imparts the desired plasticity at low temperatures.

Our lubricant is particularly designed as a plug valve lubricant for use on steam lines and the like. It is also very useful as a high pressure lubricant, particularly where high temperatures are encountered and where water soluble lubricants would be undesirable.

While we have disclosed a preferred embodiment of our invention it should be understood that we do not limit ourselves to any details except as defined by the following claims, which should be construed as broadly as the prior art will permit.

We claim:

1. A lubricant comprising about 35% to 65% graphite, about 2% to 15% anhydrous lime soap, and about 15% to 45% lead mahogany soap.

2. A lubricant comprising about one part of lime soap, seven parts of lead mahogany soap and twelve parts of amorphous graphite.

3. A lubricant consisting essentially of about amorphous graphite, about 5% substantially LAWRENCE C. BRUNSTRUM. WILLIAM P. HILLIKER. 

